Bit of Luck (Sp): You can touch a willing creature as a standard action, giving it a bit of luck. For the next round, any time the target rolls a d20, he may roll twice and take the more favorable result. You can use this ability a number of times per day equal to 3 + your Wisdom modifier.

It doesn't say this only works for ONE roll. It implies it would work for any and all rolls for that round. Soo.. if say a character had 4 attacks that round they got to use 'bit of luck', they'd get to roll twice for each attack (and potentially other rolls as well), yes?

It works on EVERY d20 roll on their turn. So if they make 1 skill check, 1 save, and 4 attacks, that's 12 d20's being rolled.

This is why it's the best cleric power in the game.

Not just on your turn, for one round. So you get to roll twice for saving throws and any d20 rolls that you make between the time the cleric uses the power and just before same initiative count on the following round.

To some it may seem like a broken power, but in reality it isn't. Economy of actions is everything in Pathfinder. As far as a Cleric using Bit of Luck on himself in combat, using a Standard Action to re-roll dice doesn't have a significantly positive impact on damage output. If fact, using that standard action to attack is more effective than using it to give yourself a chance to roll the dice again for the same action next round. Put another way, it's exactly like choosing between rolling 2d6 and taking the best one, or rolling 2d6 and adding them together. Besides, thinking outside the box, if you have the power to give someone else a Bit of Luck for their full next round, why are you somehow a less valid recipient than them? It's somehow less broke for the cleric to stand by and give the Fighter with 6 attacks a Bit of Luck every single round than it is for the Cleric to use it on himself every OTHER round? The best Cleric attacks don't even involve a D20 roll! "Save vs Implosion"... 'nuff said.

Let your Clerics have some luck if they want. They're the ones paying the Standard Action for it.

Bit of Luck really shines OUTSIDE of combat, when you want to minimize the probability of a really bad roll. The one for law domain that makes you 'take 11' is similarly good in such situations. Make sure you have one on hand if you do contact other plane with a GM that won't let you take 10 :-)

The explanations above seem to indicate this power could not be used by the caster to roll twice for an attack.

My cleric could whack his warrior buddy in round 1, who would get 2 rolls on every d20 attempt until my initiative in round 2.

But my cleric could not whack himself in round 1 and get two attack rolls in round 2. Based on my understanding of actions - My cleric couldn't use this on himself (standard action) and then pick a lock, climb a wall, tell a lie, or any other skill check that is a standard action. He COULD cast it and then move (and attempt a stealth check on that move).

Bit of Luck is good for a Reach Cleric build. You can not use Bit of Luck to enhance your own attacks during your combat round. Using the ability requires your Standard Action, leaving you no remaining attack actions, and it runs out at the start of your next turn. However, a reach-style cleric can use Bit Of Luck on self, do dangerous stuff, set up for AoOs, and get 2 rolls on each AoO. Also, Bit of Luck gives two saving throws, so it's a really handy defensive ability.

Finally, the magic item Headband of Fortune's Favor deserves honorable mention. It increases the duration of Bit of Luck from 1 round to 2 rounds.

I disagree, rounds don't work like that. They're consecutive six second periods in which every participant gets a turn to act.

You start counting from the first second of the 24 hours, subjectively defining the moment you start counting as 0 seconds. However, you're already, objectively, in a round when you use the ability and you surely can't say that the round you're already in is both the current and next round?

Besides, if that was the intent why wouldn't they just say 'For 1 round'? That would have been a lot simpler and taken less space.

Aioran actually makes a fair point. However that interpretation creates an anomaly depending on where in the initiative order the cleric is acting.

If the cleric is acting at the end of the initiative, her Bit of Luck activates immediately. If the cleric acts at the start of the initiative, Bit of Luck will take nearly six seconds before it starts.

Casting Bit of Luck on, say, a friendly fighter would have significant implications depending on where in the initiative order the cleric is acting. For this reason, I think that it more sensible to interpret the duration as "starting immediately for the next six seconds".

To Zhayne, the analogous term would be "For the next day", not "For the next 24 hours". Today is one day. "The next day" could be interpreted as tomorrow. However this interpretation, while reasonable, runs into the same anomaly as a Bit Of Luck.

Ummm... no. The rule that clarifies this was actually already posted and linked to earlier in this thread. See Grick's post early in the thread, quoting the Combat chapter of the Core Rulebook. Effects that last a round go from when they begin to just before the same initiative count of the following round.

Axl is correct that "for the next round" is analogous to "for the next day". The mistake is assuming that the phrase "for the next day" only has one interpretation, ie "the next day" after today is tomorrow, beginning at midnight. Even if we accept that we're talking about tomorrow, choosing midnight as a starting point is pretty arbitrary. Some cultures count days as beginning at dawn. The Jewish calendar counts a day as sunset through sunset.

But that's not the only way to read "for the next day". Since the word "day" has several dictionary definitions, one of which is "a division of time equal to 24 hours" (from Dictionary.com), "the next day" could also mean "the next 24 hours", which goes back to Zhayne's interpretation.

Thus, the phrases "the next day" and "the next round" are ambiguous enough to depend on context. In this case, it makes no sense for a magic power to not activate immediately unless its description specifically says there's a delay in activation. No other power in the game has a delay in activation, unless it explicitly says so. So it begins as soon as the cleric touches someone with it, and lasts for one round, ending just before the cleric's turn on the same initiative count of the following round.

There is a headband slot item, the headband of fortunes favor, that extends the duration of luck bonuses, specifically including the luck domain power, by 1 round. Costs 8k or so and also gives a +1 luck bonus to saving throws. It would probably not be efficient but you could gain the domain's benefit for yourself with the item, or give it to a friend who might not be using their headband slot.